Vehicle Routing Problem with Both Time Window and Limited Number of Vehicles (m-VRPTW) is an useful extension of VRPTW problem in real applications. We propose an improved Greedy Randomized Adaptive Search Procedure (GRASP) framework by techniques including multiple initialization and solution reuse. Furthermore, a new technique of smoothed dynamic tabu search is embedded into the GRASP to improve the performance. The experimental results for benchmark data show that the new algorithm can solve the m-VRPTW problem better than the published algorithm in accuracy.